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1.
J Biomech ; : 109729, 2020 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-32147239

RESUMO

In articular cartilage, the function of chondrocytes is strongly related to their zone-specific microniche geometry defined by pericellular matrix. Microniche geometry is critical for regulating the phenotype and function of the chondrocyte in native cartilage and tissue engineering constructs. However the role of microniche geometry in the mechanical properties and calcium signaling of chondrocytes remains unknown. To recapitulate microniche geometry at single-cell level, we engineered three basic physiological-related polydimethylsiloxane (PDMS) microniches geometries fabricated using soft lithography. We cultured chondrocytes in these microniche geometries and quantified cell mechanical properties using atomic force microscopy (AFM). Fluorescent calcium indicator was used to record and quantify cytosolic Ca2+ oscillation of chondrocytes in different geometries. Our work showed that microniche geometry modulated the mechanical behavior and calcium signaling of chondrocytes. The ellipsoidal microniches significantly enhanced the mechanical properties of chondrocytes compared to spheroidal microniche. Additionally, ellipsoidal microniches can markedly improved the amplitude but weakened the frequency of cytosolic Ca2+ oscillation in chondrocytes than spheroidal microniche. Our work might reveal a novel understanding of chondrocyte mechanotransduction and therefore be useful for designing cell-instructive scaffolds for functional cartilage tissue engineering.

2.
Acta Pharm ; 70(3): 399-409, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32074070

RESUMO

Curcumin has been proved to inhibit cell proliferation and induce cell apoptosis in non-small cell lung cancer (NSCLC). However, little is known about antimetastatic effects and molecular mechanisms of curcumin in NSCLC. In this study, we investigated the involvement of miR-206 in curcumin's anti-invasion and anti-migration in NSCLC. Cell proliferation was determined by MTT assay. Cell migration and invasion were analyzed by wound healing assay and transwell assay. MiRNA-206 expression was detected by real-time PCR. Western blot was used to detect the protein expression of PI3K/AKT/mTOR signaling pathway. Curcumin significantly inhibited migration and invasion in A549 cells, accompanied by significantly elevated miR-206 expression. Overexpression of miR-206 could inhibit migration and invasion of A549 cells, but it could also significantly decrease the phosphorylation levels of mTOR and AKT. The inhibition of miR-206 promoted cell migration, invasion and increased the phosphorylation level of mTOR and AKT. Furthermore, miR-206 mimics improved the inhibitory effects of curcumin on cell migration, invasion and the phosphorylation level of mTOR and AKT in A549 cells. On the contrary, MiR-206 inhibitors reversed the inhibitory effects of curcumin on cell migration, invasion and the phosphorylation level of mTOR and AKT. In conclusion, curcumin inhibited cell invasion and migration in NSCLC by elevating the expression of miR-206 which further suppressed the activation of the PI3K/AKT/mTOR pathway.

3.
Ann Palliat Med ; 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32075402

RESUMO

Human epidermal growth factor receptor 2 (HER2) mutation and amplification are distinct molecular targets in lung cancer, but the specific targeted therapy for their coexistence is undetermined. Personalized targeted therapy is based on mutation type, with different mutations requiring different treatment. A 64-year-old Chinese woman was diagnosed with advanced lung adenocarcinoma. She was determined as having insertion mutations in exon 20 of the HER2 gene (c.2326G > TTGT) by the amplification refractory mutation system (ARMS) and HER2 gene amplification (HER2/CEP17 ratio 2.6) by fluorescence in situ hybridization (FISH). Thereafter, she was treated with afatinib as first-line therapy, to which she responded. After 2 months, the tumor lesion decreased in size. Computed tomography (CT) follow-up showed stable lung lesions, although she later developed multiple brain metastases and subsequently died of brain failure. Lung adenocarcinoma with coexistent HER2 mutation and amplification is relatively uncommon and has no reported cases on targeted therapy. This case was important because it showed effective response to afatinib and provides evidence to help clinicians identify the therapeutic regimen for such patients.

4.
Biomed Pharmacother ; 122: 109763, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31918288

RESUMO

Emerging evidence suggests that cinobufagin, an active ingredient in Venenum Bufonis, inhibits cell proliferation in several tumor cells. However, the anti-tumor effect of cinobufagin on nasopharyngeal carcinoma and the underlying molecular mechanisms are still unclear. In this study, we found that cinobufagin significantly inhibits the proliferation of nasopharyngeal carcinoma HK-1 cells. Further analyses demonstrated that cinobufagin induces cell cycle arrest at the S phase in HK-1 cells through downregulating the levels of CDK2 and cyclin E. Moreover, cinobufagin significantly downregulates the protein level of Bcl-2 and upregulates the levels of Bax, subsequently increasing the levels of cytoplasmic cytochrome c, Apaf-1, cleaved PARP1, cleaved caspase-3, and cleaved caspase-9, leading to HK-1 apoptosis. Furthermore, we found that cinobufagin significantly increases ROS levels and decreases the mitochondrial membrane potential in HK-1 cells. Collectively, these data imply that cinobufagin induces cell cycle arrest at the S phase and induces apoptosis through increasing ROS levels, thereby inhibiting cell proliferation in HK-1 cells. Therefore, cinobufagin is a promising bioactive agent that may contribute to the development of treatment strategies of nasopharyngeal carcinoma.

5.
Environ Pollut ; 256: 113416, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677871

RESUMO

Marine oil spill often causes contamination of drinking water sources in coastal areas. As the use of oil dispersants has become one of the main practices in remediation of oil spill, the effect of oil dispersants on the treatment effectiveness remains unexplored. Specifically, little is known on the removal of dispersed oil from contaminated water using conventional adsorbents. This study investigated sorption behavior of three prototype activated charcoals (ACs) of different particle sizes (4-12, 12-20 and 100 mesh) for removal of dispersed oil hydrocarbons, and effects of two model oil dispersants (Corexit EC9500A and Corexit EC9527A). The oil content was measured as n-alkanes, polycyclic aromatic hydrocarbons (PAHs), and total petroleum hydrocarbons (TPHs). Characterization results showed that the smallest AC (PAC100) offered the highest BET surface area of 889 m2/g and pore volume of 0.95 cm3/g (pHPZC = 6.1). Sorption kinetic data revealed that all three ACs can efficiently adsorb Corexit EC9500A and oil dispersed by the two dispersants (DWAO-I and DWAO-II), and the adsorption capacity followed the trend: PAC100 > GAC12 × 20 > GAC4 × 12. Sorption isotherms confirmed PAC100 showed the highest adsorption capacity for dispersed oil in DWAO-I with a Freundlich KF value of 10.90 mg/g∙(L/mg)1/n (n = 1.38). Furthermore, the presence of Corexit EC9500A showed two contrasting effects on the oil sorption, i.e., adsolubilization and solubilization depending on the dispersant concentration. Increasing solution pH from 6.0 to 9.0 and salinity from 2 to 8 wt% showed only modest effect on the sorption. The results are useful for effective treatment of dispersed oil in contaminated water and for understanding roles of oil dispersants.


Assuntos
Hidrocarbonetos/química , Poluição por Petróleo , Poluentes Químicos da Água/química , Adsorção , Alcanos , Carvão Vegetal/química , Cinética , Petróleo/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Hidrocarbonetos Policíclicos Aromáticos/química , Salinidade , Água do Mar/química , Tensoativos/química , Poluentes Químicos da Água/análise
6.
Angew Chem Int Ed Engl ; 59(2): 819-825, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31688992

RESUMO

Integrated differential phase-contrast scanning transmission electron microscopy (iDPC-STEM) is capable of directly probing guest molecules in zeolites, owing to its sufficient and interpretable image contrast for both heavy and light elements under low-dose conditions. This unique ability is demonstrated by imaging volatile organic compounds adsorbed in zeolite Silicalite-1; iDPC-STEM was then used to investigate molybdenum supported on various zeolites including Silicalite-1, ZSM-5, and mordenite. Isolated single-Mo clusters were observed in the micropores of ZSM-5, demonstrating the crucial role of framework Al in driving Mo atomically dispersed into the micropores. Importantly, the specific one-to-one Mo-Al interaction makes it possible to locate Al atoms, that is, catalytic active sites, in the ZSM-5 framework from the images, according to the positions of Mo atoms in the micropores.

7.
Cancer Med ; 9(3): 988-998, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31846222

RESUMO

OBJECTIVE: Stage I-II uterine papillary serous carcinoma (UPSC) has aggressive biological behavior and leads to poor prognosis. However, clinicopathologic risk factors to predict cancer-specific survival of patients with stage I-II UPSC were still unclear. This study was undertaken to develop a prediction model of survival in patients with early-stage UPSC. METHODS: Using Surveillance, Epidemiology, and End Results (SEER) database, 964 patients were identified with International Federation of Gynecology and Obstetrics (FIGO) stage I-II UPSC who underwent at least hysterectomy between 2004 and 2015. By considering competing risk events for survival outcomes, we used proportional subdistribution hazards regression to compare cancer-specific death (CSD) for all patients. Based on the results of univariate and multivariate analysis, the variables were selected to construct a predictive model; and the prediction results of the model were visualized using a nomogram to predict the cancer-specific survival and the response to adjuvant chemotherapy and radiotherapy of stage I-II UPSC patients. RESULTS: The median age of the cohort was 67 years. One hundred and sixty five patients (17.1%) died of UPSC (CSD), while 8.6% of the patients died from other causes (non-CSD). On multivariate analysis, age ≥ 67 (HR = 1.45, P = .021), tumor size ≥ 2 cm (HR = 1.81, P = .014) and >10 regional nodes removed (HR = 0.52, P = .002) were significantly associated with cumulative incidence of CSD. In the age ≥67 cohort, FIGO stage IB-II was a risk factor for CSD (HR = 1.83, P = .036), and >10 lymph nodes removed was a protective factor (HR = 0.50, P = .01). Both adjuvant chemotherapy combined with radiotherapy and adjuvant chemotherapy alone decreased CSD of patients with stage I-II UPSC older than 67 years (HR = 0.47, P = .022; HR = 0.52, P = .024, respectively). The prediction model had great risk stratification ability as the high-risk group had higher cumulative incidence of CSD than the low-risk group (P < .001). In the high-risk group, patients with post-operative adjuvant chemoradiotherapy had improved CSD compared with patients who did not receive radiotherapy nor chemotherapy (P = .037). However, there was no such benefit in the low-risk group. CONCLUSION: Our prediction model of CSD based on proportional subdistribution hazards regression showed a good performance in predicting the cancer-specific survival of early-stage UPSC patients and contributed to guide clinical treatment decision, helping oncologists and patients with early-stage UPSC to decide whether to choose adjuvant therapy or not.

8.
Sci Rep ; 9(1): 19781, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31874992

RESUMO

To quantify the hydraulic characteristics of overland flow on gravel-covered slopes, eight flow discharges (Q) (8.44-122 L/min), five slope gradients (J) (2°-10°) and four gravel coverage degrees (Cr) (0-30%) were examined via a laboratory flume. The results showed that (1) gravel changed flow regime. Gravel increased the Reynolds number (Re) by 2.94-33.03%. Re were less affected by J and positively correlated with Cr and Q. Gravel decreased the Froude number (Fr) by 6.83-77.31%. Fr was positively correlated with Q and J and negatively correlated with Cr. (2) Gravel delayed the flow velocity (u) and increased the flow depth (h) and flow resistance (f). Gravel reduced u by 1.20-58.95%. u was positively correlated with Q and J and negatively correlated with Cr. Gravel increased h by 0.12-2.41 times. h was positively correlated with Q and Cr and negatively correlated with J. Gravel increased f by 0.15-18.42 times. f were less affected by J, positively correlated with Cr and negatively correlated with Q. (3) The relationships between hydraulic parameters and Q, J and Cr identified good power functions. Hydraulic parameters were mainly affected by Cr. These results can guide the ecological construction of soil and water conservation.

9.
J Phys Chem Lett ; 10(24): 7594-7602, 2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31769991

RESUMO

Semiconductor-metal hybrid nanostructures present an exotic class of nonlinear optical materials due to their potential optoelectronic applications. However, most studies to date focus on their total optical responses instead of contributions from individual nonlinear orders. In this Letter, we present a theoretical study on the third-order nonlinear optical absorption of a hybrid colloidal semiconductor quantum dot (SQD)-metal nanoparticle (MNP) system. We develop a novel analytic treatment based on the nonlinear density matrix equation and derive a closed-form expression for the optical susceptibility. Our study identifies the parameter space that governs the system's optical transition from being a saturable absorber to a Fano-enhanced absorber. We attribute this transition to the plasmon-mediated self-interaction of the SQD. The findings provide a valuable guideline for optimized designs of functional nanophotonic devices based on SQD-MNP hybrid structures.

10.
Diagn Pathol ; 14(1): 116, 2019 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-31647020

RESUMO

BACKGROUND: Gastrointestinal stromal tumors (GISTs), a type of mesenchymal tumor in the gastrointestinal tract, are believed to be closely associated with PDGFRA and C-KIT mutations. Schwannoma in the stomach, which is an unusual location, is a rare disorder. The simultaneous occurrence of the two diseases is rarer than metachronous occurrences, and its pathological characteristics have not been reported to date. We present a case report on a patient with simultaneous coexistence of gastric schwannoma and GISTs. CASE PRESENTATION: A 39-year-old female visited our hospital complaining of intermittent abdominal pain for the previous 3 months. CT revealed a 3.4 cm slight homogeneous enhancement in the lesser curvature of the stomach; the mass was nodular soft tissue, which was removed by radical surgery. Two solid tumors with different volumes were located in the stomach. Histologically and immunohistochemically different, the larger tumor consisted of spindle cells surrounded by a peripheral lymphoid cuff, and was positive for S-100. The larger tumor was therefore classified as a gastric schwannoma. The smaller tumor was composed of medium-sized round, oval cells with amphiphilic granular cytoplasm; vacuolization was also observed. The tumor cells were positive for DOG1 and sporadically positive for CD34 and CD117. Hence, the smaller tumor was diagnosed as epithelioid GISTs. Sanger sequencing revealed that the GIST tumor cells contained a deletion mutation (c.2527_2538 del12,843-846del4), which was located in exon 18 of PDGFRA. CONCLUSION: GISTs combined with gastric schwannoma are a considerably rare subgroup of gastric tumors. Related clinical research is comparatively weak, and the mechanism remains unknown. We reviewed related articles to provide knowledge to improve the correct identification, diagnosis and management of patients with gastric cancer. All pathologists involved in the diagnosis and clinicians involved in the treatment should be aware of this new kind of disease pattern to improve their understanding of the disease.

11.
Front Oncol ; 9: 853, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31552178

RESUMO

Emerging evidence has shown that cinobufagin, as an active ingredient of Venenum Bufonis, inhibits tumor development. The aim of this study was to investigate the inhibitory effects of cinobufagin on A375 human malignant melanoma cells. MTT and colony formation assays showed that cinobufagin significantly inhibited A375 cell proliferation and cell colony formation. Additional studies demonstrated that cinobufagin markedly increased the levels of ATM serine/threonine kinase (ATM) and checkpoint kinase 2 (Chk2) and decreased the levels of cell division cycle 25C (CDC25C), cyclin-dependent kinase 1 (CDK1), and cyclin B, subsequently inducing G2/M cell cycle arrest in A375 cells. Moreover, cinobufagin clearly inhibited the levels of phosphoinositide 3-kinase (PI3K), phosphorylated PI3K (p-PI3K), AKT, p-AKT, and B-cell lymphoma 2 (Bcl-2). By contrast, it increased the levels of Bcl-2-associated death promoter, Bcl-2-associated X, cytoplasmic cytochrome C, and apoptotic protease activating factor 1, leading to increased levels of cleaved caspase-9 and cleaved caspase-3, resulting in the apoptosis of A375 cells. Together, these results indicate that cinobufagin can induce cell cycle arrest at the G2/M phase and apoptosis, leading to inhibition of A375/B16 cell proliferation. Thus, cinobufagin may be useful for melanoma treatment.

12.
Front Pharmacol ; 10: 905, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31474863

RESUMO

Objective: This study compared the pharmacokinetics (PK), safety, and immunogenicity of the biosimilar TAB008 monoclonal antibody to bevacizumab (Avastin®) in normal healthy Chinese male volunteers. Methods: In this randomized, double-blind, parallel controlled study, a total of 100 healthy Chinese male subjects were randomized (1:1) to receive a single 1 mg/kg intravenous dose of TAB008 or Avastin® over a 90-min infusion. The subjects were followed for 99 days after drug administration. Primary endpoints were bioequivalence of major pharmacokinetic parameters (AUC0-t and AUC0-∞) and maximum observed serum concentration (Cmax). Secondary endpoints included safety and immunogenicity parameters. Results: The two groups of test subjects (49 subjects in the TAB008 group and 50 subjects in the Avastin® group) were well matched in regards to all demographic and baseline characteristics. The treatment group ratios of LS geometric means for the three primary PK parameters were fully contained within the bioequivalence limits of 80.00-125.00% (90% CI was 103.66-118.33% for Cmax, 94.32-111.72% for AUC0-t, and 94.69-112.23% for AUC0-∞). Treatment-emergent adverse events (TEAEs) were reported for 24 (49.0%) subjects in the TAB008 group and 22 (44.0%) subjects in the Avastin® group. TEAEs related to the study drug were reported for 19 (38.8%) subjects in the TAB008 group and 19 (38.0%) subjects in the Avastin® group. National Cancer Institute-Common Terminology Criteria for Adverse Events (NCI-CTCAE) Grade 3 TEAEs were reported for 1 (2.0%) subject in the TAB008 group and 3 (6.0%) subjects in the Avastin® group. There were no Grade 4 or 5 TEAEs or serious adverse events (SAEs) during the study. Anti-drug antibody generation was reported once only in each group, and neutralizing antibody (Nab) analysis was negative upon follow-up. Conclusion: TAB008 attained pharmacokinetic similarity to bevacizumab, and was safe and well tolerated.

13.
World J Gastroenterol ; 25(30): 4199-4212, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31435173

RESUMO

The huge prognostic difference between early and late stage hepatocellular carcinoma (HCC) is a challenging diagnostic problem. Alpha-fetoprotein is the mostly widely used biomarker for HCC used in the clinic, however it's sensitivity and specificity of is not optimal. The development and application of multiple biotechnologies, including next generation sequencing, multiple "omics" data, that include genomics, epigenomics, transcriptomics, proteomics, metabolomics, metagenomics has been used for HCC diagnostic biomarker screening. Effective biomarkers/panels/models have been identified and validated at different clinical levels. A large proportion of these have a good diagnostic performance for HCC, especially for early HCC. In this article, we reviewed the various HCC biomarkers derived from "omics" data and discussed the advantages and disadvantages for diagnosis HCC.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma Hepatocelular/diagnóstico , Biologia Computacional/métodos , Ensaios de Triagem em Larga Escala/métodos , Neoplasias Hepáticas/diagnóstico , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Ensaios Clínicos como Assunto , Detecção Precoce de Câncer/métodos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Valor Preditivo dos Testes , Sensibilidade e Especificidade
14.
Chem Commun (Camb) ; 55(66): 9853-9856, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31364672

RESUMO

A rationale for designing selective NO reduction catalysts with strong alkali resistance was proposed, based on extensive studies of a variety of catalysts with common characteristics of separate catalytically active sites and alkali-trapping sites.

15.
Kaohsiung J Med Sci ; 35(11): 659-671, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31332950

RESUMO

Prostate cancer (PCa) remains the secondary highest cause of cancer-related death in the United States in men. It has been reported that microRNAs can serve as key regulators in tumor development and progression in various cancers including PCa. In this study, we examined the effect of miR-498 on proliferation, radiosensitivity, invasion, and migration of PCa cells. The proliferation of LNCaP and DU-145 PCa cells with altered expression of miR-498 was evaluated by MTT assay. The invasion and migration of LNCaP and DU-145 PCa cells were assess by matrigel invasion assay and transwell migration assay. The protein expression level in PCa cells was examined by western blot. The function of miR-498 on radiation-induced apoptosis in LNCaP and DU-145 PCa cells was detected by Caspase-Glo3/7 assay. Forced expression of miR-498 improved the proliferation, invasion and migration in PCa cells. Furthermore, miR-498 decreased the sensitivity of PCa cells after ionizing radiation treatment. MiR-498 reduced the radiation-induced apoptosis in PCa cells by regulation of BAX and Bcl-2 expression. Meanwhile, miR-498 altered the expression of E-cadherin, N-cadherin, snail, and Vimentin in both LNCaP and DU-145 PCa cells and regulated epithelial to mesenchymal transition (EMT). Further study showed that aberrant expression of miR-498 changed the expression levels of phosphatase and tensin homolog and p-AKT in LNCaP and DU-145 PCa cells. In a summary, miR-498 displayed important roles in tumor development and progression in PCa cells, and might act as a potential prognostic biomarker and predict radiotherapy response in PCa.

16.
Biomolecules ; 9(7)2019 07 11.
Artigo em Inglês | MEDLINE | ID: mdl-31336757

RESUMO

Malignant melanoma is the most lethal type of skin cancer. Previous studies have shown that ailanthone has potent antitumor activity in a variety of cell lines. However, the anti-tumor effect of ailanthone on malignant melanoma remains unclear. To investigate the anti-tumor mechanisms of ailanthone in human melanoma B16 and mouse melanoma A375 cells, the cell counting kit-8 assay, colony formation assay, DNA content analysis, Hoechst 33258, and Annexin V-FITC/PI staining were used to assess cell proliferation, cell cycle distribution, and cell apoptosis, respectively. Western blotting was performed to evaluate the expression of cell cycle- and apoptosis-related proteins and regulatory molecules. The results showed that ailanthone significantly inhibited melanoma B16 and A375 cell proliferation as well as remarkably induced cell cycle arrest at the G0-G1 phase in B16 cells and the G2-M phase in A375 cells in a dose-dependent manner. Further investigation revealed that ailanthone promoted the expression of p21 and suppressed the expression of cyclin E in B16 cells or cyclin B in A375 cells through the PI3K-Akt signaling pathway. In addition, ailanthone induced B16 and A375 cell apoptosis via a caspase-dependent mechanism. Further studies showed that ailanthone remarkably downregulated Bcl-2 and upregulated Apaf-1 and Bax, and subsequently increased mitochondrial membrane permeabilization and released cytochrome c from the mitochondria in B16 cells and A375 cells. Taken together, ailanthone induces cell cycle arrest via the PI3K-Akt signaling pathway as well as cell apoptosis via the mitochondria-mediated apoptotic signaling pathway. Ailanthone may be potentially utilized as an anti-tumor agent in the management of malignant melanoma.

17.
Biomolecules ; 9(8)2019 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-31349651

RESUMO

The main chemical component of cannabis, cannabidiol (CBD), has been shown to have antitumor properties. The present study examined the in vitro effects of CBD on human gastric cancer SGC-7901 cells. We found that CBD significantly inhibited the proliferation and colony formation of SGC-7901 cells. Further investigation showed that CBD significantly upregulated ataxia telangiectasia-mutated gene (ATM) and p53 protein expression and downregulated p21 protein expression in SGC-7901 cells, which subsequently inhibited the levels of CDK2 and cyclin E, thereby resulting in cell cycle arrest at the G0-G1 phase. In addition, CBD significantly increased Bax expression levels, decreased Bcl-2 expression levels and mitochondrial membrane potential, and then upregulated the levels of cleaved caspase-3 and cleaved caspase-9, thereby inducing apoptosis in SGC-7901 cells. Finally, we found that intracellular reactive oxygen species (ROS) increased after CBD treatment. These results indicated that CBD could induce G0-G1 phase cell cycle arrest and apoptosis by increasing ROS production, leading to the inhibition of SGC-7901 cell proliferation, thereby suggesting that CBD may have therapeutic effects on gastric cancer.

18.
Bioresour Technol ; 291: 121862, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31357047

RESUMO

This study evaluated the feasibility of microbial fuel cells (MFCs) for simultaneous electricity generation and degradation of phenolic compounds. The voltage generation was inhibited by 36.18-63.90%, but the degradation rate increased by 146.15-392.31% when the initial concentration of syringic acid (SA), vanillic acid (VA), and 4-hydroxybenzoic acid (HBA) increased from 0.3 to 3.0 g/L. The collaboration among the functional microbes significantly enhanced the degradation rate of parent compounds and their intermediates in MFCs systems, while the accumulated intermediates severely inhibited their complete mineralization in fermentative systems. High-throughput sequencing showed that the growth of fermentative bacteria prevailed, but electrogenic bacteria were inhibited in the anode microbial community (AMC) under high concentrations of phenolic compounds (3.0 g/L). These findings provide a better understanding of the dynamic shift and synergy effects of the AMC to evaluate its potential for the treatment of phenolic-containing wastewater.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Microbiota , Fenóis/metabolismo , Eletricidade , Eletrodos , Fermentação
19.
Chemosphere ; 234: 260-268, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31220659

RESUMO

Phenolic compounds are problematic byproducts generated from lignocellulose pretreatment. In this study, the feasibility degradation of syringic acid (SA), vanillic acid (VA), and 4-hydroxybenzoic acid (HBA) by Bio-Electro-Fenton (BEF) system with a novel Fe-Mn/graphite felt (Fe-Mn/GF) composite cathode were investigated. The nano-scale Fe-Mn multivalent composite catalyst with core shell structure distributed more evenly on GF surface to form a catalyst layer with higher oxygen reduction reaction performance. Accordingly, the maximum power density generated with Fe-Mn/GF cathode was 48.1% and 238.9% higher than Fe/GF and GF respectively, which further enhanced the in situ generation of H2O2 due to the superiority of nano-scale core shell structure and synergistic effect of Fe and Mn species. The degradation efficiency of the three phenolic compounds in the BEF system could reached 100% after optimization of influencing parameters. Furthermore, a possible SA degradation pathway by BEF process in the present system was proposed based on the detected intermediates. These results demonstrated an efficient approach for the degradation of phenolic compounds derived from lignocellulose hydrolysates.


Assuntos
Eletroquímica , Eletrodos , Grafite/química , Peróxido de Hidrogênio , Ferro/química , Manganês/química , Fenóis/química , Catálise
20.
PeerJ ; 7: e6992, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31205823

RESUMO

Small heat shock proteins (sHSPs) are probably the most diverse in structure and function among the various super-families of stress proteins, and they play essential roles in various biological processes. The sweet potato whitefly, Bemisia tabaci (Gennadius), feeds in the phloem, transmits several plant viruses, and is an important pest on cotton, vegetables and ornamentals. In this research, we isolated and characterized three α-crystallin/sHSP family genes (Bthsp19.5, Bthsp19.2, and Bthsp21.3) from Bemisia tabaci. The three cDNAs encoded proteins of 171, 169, and 189 amino acids with calculated molecular weights of 19.5, 19.2, and 21.3 kDa and isoelectric points of 6.1, 6.2, and 6.0, respectively. The deduced amino acid sequences of the three genes showed strong similarity to sHSPs identified in Hemiptera and Thysanoptera insects species. All three sHSPs genes from Bemisia tabaci lacked introns. Quantitative real-time PCR analyses revealed that the three BtsHSPs genes were significantly up-regulated in Bemisia tabaci adults and pupae during high temperature stress (39, 41, 43, and 45 °C) but not in response to cold temperature stress (-6, -8, -10, and -12 °C). The expression levels of Bthsp19.2 and Bthsp21.3 in pupae was higher than adults in response to heat stress, while the expression level of Bthsp19.5 in adults was higher than pupae. In conclusion, this research results show that the sHSP genes of Bemisia tabaci had shown differential expression changes under thermal stress.

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